Chair height adjustment means



1955 5. J. NOCEK ETAL 3,

CHAIR HEIGHT ADJUSTMENT MEANS Filed Jan. 22, 1963 gg-k F 1+- 2 54,- l 4 F26 7 75 so 54 54 i 32 wlllli al -rinllllll/ INVENTORS Stanley J.' Nocek George 11'. Stall 3,169,744 CHAIR IEIGHT ADJUSTMENT MEAN Stanley J. Nocek, Northlake, and'George H. Stell, Elm.- hurst, 11L, assignors to Precision Metal Workers, Chicago, IllL, a co-partnership composed of Ralph Robinson and K. 0. Robinson Filed Jan. 22, 1963, Ser. No. 253,137

3 Claims (Cl. 243-405) V This invention relates to chair height adjustment devices and methods and particularly to improvements in chairheightadjustment devices to be used in ofiice swivel chairs.

Ofiice swivel chairs presently available and used are almost always provided with height adjustment devices so that a given chair may be easily and rapidly adjusted v to a height most comfortable for the intended user. A

very widely usedheight adjustment device. embodies a:

adjustment mechanism than has heretofore been avail able. r V -,Another object of this invention is the provision in a chair having a chair body'and a pedestal, of a unitary l handwhe'el in combination with a handwheel type chair height adjustment mechanism which. handwheel may be formed from a' single flat sheet, such assteel, which handwheel has asingle thread andis adapted. to move along a United States Patent means ice stantially alongline 55.of FIG. 6, showing the handwheel thread; v FIG. 6 is a bottom view of thehandwheel of FIG. 2;

. FIG. 7 is a partial sectional view of the handwheel thread of'FIG. 6 taken substantiallyalong line 77.of FIG. 6; and I,

FIG. 8 is a plan view, partially in section, of the bearins of FIG. 2.

The height adjustment mechanism It useful with the chair C ofFlG. 1 is showna's being located below a chair ,body 1 2 and above a chair pedestal, whichis rollingly supported upon a floor F by casters 16.

7 (FIG. .1) upon which the chair body 12 is balanced. The. chair body supporting mechanism is constructed 'to permit A presently preferred embodiment of the height adjustment mechanism 10 of this invention, as best seen in .FIG. 2, includes a threaded shaft 18 having a generally helical thread 20 and a keyWay ZZ which extendsto the root of thread 20. At its upper end shaft 18 is fixedly connected to a chair body supporting mechanism 23 the chair body 12 to rockwith respect tothe pedestal 14. Adjacent the chair pedestal 14, height adjustment mechanism it) isprovided with a pedestal hub 24. Hub 24 rests upon;the pedestal. ,It includesan annular eircular planar section 25 and an upstanding cylindricalsleeve portion 26. Cylindrical sleeve portion 26 is concentric with a bore 28 in pedestal"14.z The annular cir 'cular planar section 25 of hub 24 rests upon central portions of chair pedestal 14 to assist in stabilizing the height adjustment mechanism 10.21nd the chair body 12. It may I be connectedto chair pedestal 14 by means" such as screws threaded shaft to lower and to raise thefchair body with respect to the pedestal. Y

A further object of this-invention is the provision of a simple, novel chair height adjustment mechanism having an integral handwheel formed from a" single sheet' of metal and novel recessedbearing means, in which the handwheel has a single thread and is adapted to engage a threaded shaft directly to move a chair body upwardly and downwardly along that threaded shaft with respect to a chair pedestal.

Yet another object of this invention is to provide" a novel method of forming a unitary handwheel for use in a chair height adjustment mechanism comprising remov:

ing a circular segment centrally of apiece of planar sheet material having a planar upper surface and a planar lower surface, swaging the spaced. parallel edges of'said opening to form spaced converging edgesterminating in a common cylindrical edge, all of said edges lying between said upper surface and said lower surface; trimming and slotting said edges, and displacing said edges withrespect to'said planar sheet material so that said edges lie along a common helical path. and sothat at least a portion of. Said edges lie outside the planes defined by said upperand lower surfaces.

Still other objects anda dvantages of invention will become apparent from the following description and drawings fwhich: v r j 3 FIG. .1 illustrates an otlice swivel chairv of the type with which a height adjustment device of this be used; V FlG. 2 is an enlargedside elevation, partially in section,

of a height adjustment device of this invention;

invention may ceived in suitable threaded openings provided in hub; sleeve-26 and housing'segment 32. It is'therefore ap- 1 constructed in accordance with this invention.

(not shown).

, Extending upwardly fronrhub and llyin g within; sleeve portion 26 is a shaft housing 3%. Shaft housing 3% includes -.a cylindrical, segment 32 and an upper flange segment 34. Flangesegment 34 is adapted to rest upon the upper end of hub sleeve portion 26. Housing-cylindrical segment 32 is very slightly larger than the thread diameterof shaft 13 and is adapted, therefore, to guidingly and slidably receive shaft'lS. Shaft housing 30 and hub 24 may-be'locked to each other by a set screw 36*reparent that hub 24- and housing 30 form an integral unit which serves to balance chair body 12'upon pedestal 14.

They also cooperate to line pedestal bore 28 so that it' reciprocally receives. and guides shaft 18 thereby preventing wobbling' and inducing.stability in the height adjustment mechanism It), hence stability of thechair body 12 with respect to pedestal l4. 1 r

Overlying the pedestal hub 24 is a novel handwheel. 4-8 As.- is apparent, handwheel 4tl is adapted to rotateabout shaft 18'and to be moved therealong to reciprocate chair body 12 and to :cause it to be elevated and lowered. A' flange 42, welded to the bottom of handwheel 40, has a down I wardly extendingarm M -which is provided with a tapped opening in which is located a complementary threaded bolt 46, 'Bolt'46 is positio'ned so that it may'underlie circular flange segment 34 of housing'30' thereby limiting the freedom ofvertical movement of'handwheel 49 I with respect to pedestal 14, however permitting handwheel 4M0 rotate relativelyfreely with respect to pedestal 14. Bolt 46 maybe unscrewed sot hat the chair body and associated shaft may beremoved; from the pedestal. Ac-

cess to bolt 46 is proyidedjby an opening47 in the hand- FIG. 3 isapartial side section showing the handwheel in their interlocked relationship; FIG. 4 is a partial side elevation, similar to FIG. 3; lllGldisan'enlarged partial sectional View sub- Art'annular bearing48t-coa-xial with shaft 18, lies betweenthe upper'surface -o'f housing flange segment 34 andthe lower surface'of handwheel 40; Bearing 48 is of molded nylon. It includes a central annular web portion.

- and an outer'flange Flange on its upper;

UPQented Feblfi, 1965 of thecentral body portionfitlzq" I II As is'de'scepnihleinFlG iz shatt thread ZQ is an thread, trapezoidal in cross-section; That confignrat on height of'ehair body The handwheelflilrashas ta single sheet of fiat planar'ihaterial, Q It isfabricatedby loft/fer snrfacehears plil'rality of equidistantly spaced t dimples 54. 5011 the inner surface of .Web portion 50;

hearing 48 bears a key 56 which is proportioned to ride in shaft keyway zz thereby preventing relative rotational movement'hetween shaft 18 and bearing 48.

' As best seen in FIGS. 3 and 4, dimples 54 on the lovver 'face of bearing 48, bear against 'the'fiat uppe'r sur'face 58' t I of housing flange segment 34. The dimples and the'upper" I surface 533 -561 astthe' principal bearing rneans upon; which chair bodyilZ rotates withrespect top'edes'tal 14.

II Handwheel 4%), as may be appreciated from the accor n L pany'ing' descriptive drawings, is 'fonned' from a single I piece of flat sheet stock of fsilitable thickness; As best- 's'eeni in FIGS( 2' andfi, handvvheel llfincludes a gen-V erallycircular central body ,portion fili and a fiatige 62 flange -detents 64 are providedinjflange 62'to reinforce handWheeli-i) and' tofacilitategripping and rotating hand-f" Wheel 4% torchangethe' height of'chairbody 12.:

' 1 At its centenhandyyheel 4!} is provided with a mating thread for shaft thread 2i); In accordance with this inven-i V tionj handwheel'thread 79 is integral at its root 71With and is formed from the same sheet'frorn which handwheel -flitselfis formed 'Ihe thread is forniediso that its pitch V I ,f disposed substantially normally to the body portion 61 around its entire periphery. A plurality of elongated is the same; as the pitch of shaft'thread 2i) with which it g cooperates. Since thread is forrnedj integrallyfwith I v handwheel Ail, it defines but one substantially complete helix as is-best seen in'F IGS '5, J6 and '7." FIGURE 5 .shows the terminaliends'jziot thread '70.v And as; seen', in FIG; jencept at the yery ends'72of'thread'7tl, thew apex 73 of thread 7% definesacircularopening centrally proyides'inclined bearing sin-faces; upperfbearing suifaee 7fiand lowerbearing surface 76; which cooperate with;- complementary inclined" upper bearing siirface "73};and; I lower beai'in'g snrtace 80 of 'handwh'eelfthread 7fl xsinii i I .larlyanfAcme thread, to facilitate and-Jniake feasierrota tion' of the handvvheel with respecttothe'shaft. :As' 'is alsodiscernibleltrom FIG. '2, the: handylheel' thread apex 13 terminates inwardly of shaft .thread' tl very. closely a liacentitsroet. Y

Handwheelffi, in itsicentral Body portion 60, includes a plurality offfgener'ally elongated 'radially disposedd'e p'ressions '32. Depressions 32 which strengthen central v ibodyipor tion- 6i) are'spaced' to' mate Withdimplesf-S ion 'thati operation which will thread.- i i All'of that isi'done' While the thread lies in the :plane V I I of .thehody portion. Finally, the thread is brought to'that pitch whichwill enable it toeocperate with a helical'shaft thread by operating upon'it inja forming die.

Thus it is that the thread is formed so that the edges lie along a'cornn on helical path and'so that at least a portion of the edges lie outsideiofthe planes of the upper and lower surfaces 'of the central'body portion. 'With j the thread formed, the-handwheel is ready for' use'.

In operation,as handwheel this rotated, itis driven along shaft l8, byivirtuejoff-the cooperation between thread's and 79. Wherehearingsiirfaces; such as upper inclinedjsnrface 778 ofrtthe handyvheel thread 79 and the lowertinclinedsurface 7,4 of shaft thread 2%) are provid ed; the rotation of handwheel 4i! isrnade easier. The single helicalthreadfll of handwheel 40 also facilitates easier 'rotation 'than -do the plurality ofthreads normally and conventionally used in association w ith handwheel as seinbliesv Even when tested underlloads of asvmuch as V 3600;pounds, "the handwheel having butia single integral helical tbreadfwas found to resist distortion completely,

i demonstrating its completelysatisfactory"functioning in" chairheightadjustment mechanisms.

' The-single thread 'ltijhas been 'shcivn as extending above and below-the plane of the central body portion at) of-handwheel 4t}. ln fact, about l8Q ofthe'thread 'exr.

' tends'upwerdly frm'n; and about 180? of the th'read extends downwardly from, the central plane ofthecentral body'portion', m1 the ends or the thread are substantially equidistantlyspaced-trcirdfihe opposite faces of central" I body portiona'el; I It is apparent that the singlethreadrnay "be struck outupwardlyior doyvnwardlyofthe eentr'alhodyportion, if desired, f

Becausef'thread 7i eXte 7i3fclearsboth the annillar we'oStl and Outer flange'SZ of 1 bearing 48-, the recessof which is both deepenough and theupper surface of bearing 48in the manner shown in FIGSL B and 4 It is the tendencyof diinples 54 to fall into depressions 82 ;as chairbody 1; is rotated: How- I ever the depressions are not so deep that handwheel 49 is I prevented from 'rotating, Whichjbecause' bearing 435s keyedtoshaft 18, requires dimples 54 to-disengage from depressions 52 rather easilypgThus it is that hearing 48 :is, releasably locked to" handwheel. 'And when ch airl body llisjr'otated, 'because it is tin'edto shaft 718 andb'ecause shaftltt'i's keyed to bearingfiS andlbearing 48is flocked! to handWheelMl; handwheel 40 will not rotate with" ref spectjto shaft 18fand will; not aceidentally 'change the been stated; formed from firstirernoving aqcircular lsegrnentlaridfforrning' the bod-y'f flie betweeh 'the upper '2 portionand flange'62'With"-the associateddepressions-and i detents; The Acme thread' then iorrned byfplac'ing' the" handwheel 'blank- -in a, swaging die and byTfdrCirig-twoQ e malepunch members againstthe' upperandflower edges of I ""1 i the opening to' forni the tape rtcharacteristie of the'Acrne' T :Qthread; Those edge's' continue j I t and lower surfaees oii-the eentralhodyjportion and define a common cylindrical edgivertically diSPCSd 'jWlth re-r.

sipectfto' theluppe i arid lower ,surfaces of-the central body'f v xp'ortion. Negitt h inside edgeof theQthr ead-i 'isftrimmed} to the proper idiarneitei: land a "slot which w ll define the; ends of the threads" cutinthe threadtqfacihtate wide ienough toeccoinn odate thread-7t};- In that respect I seen FIG; 3 particularly. j I

Although thesingle'threadiflilhasbeenjshoivnashayin i 5 one end lying above the plane ofcentral body portion and its other end'lying'belovv-theplane'of-central body portion eilfit' is apparent that as long as the'p itchof the I jsingle thread'isthe sanreas the pitch :oftheshaft thread the handwheel will operate satisfactorily; I

.That rninori'rnodifieations I andjchan'ges rna'y hebe ne'cessaIy-iriyieW oi the follotving ela'irns r o IQ We clair'riit '7 I "j 1; In 'a chair havingra chair body ,;the height ofiwh'ich is-adju'stablg the combination:.cornprisinga chairpedestal and: a chair body rotatahlefwith respect thereto; ashaft having a continuous jhelical threadintegral therewith, II means mounting-said chai'r body upon one end of said shaft,jmeanseonnectedto'said chairpedestal tor'monnting l Vsaid shaft upon said pedestal at a'pointreniote from saidy 1 9 give the proper pitch tethe ds downwardly belovrzthe' lower 1 tace of central hotly,portionttl b'earing.48 -n1ust=be pro II porti'on'ed to receivejthreadfiilifit'isto liei again'st the lower face of the handwheelzjeentral hodyportionfltlfland dimples sd are to mate'withdepressions SZ TherefOre;

-:the outer diametersd FlG. 8) -"of central annula'r eb S0 to'fbearing 48 is g'reater than the outer'diameterof thread I 1 '73.; So alsois'the vertical di inensiohhtFIG. 2) greater 1 than thejyerticalextent of that portion of threadjtl which" v eiitends helo wcentralbody-portion60. Therefore thread I one end of said shaft, a handwheel including a central body portion, said central body portion defining a single integral helical thread of a pitch equal to the pitch of the thread of said shaft, said handwheel thread defining an opening in said central body portion and engaging said shaft thread at a point intermediate said pedestal and said chair body for reciprocating said shaft with respect to said pedestal, said handwheel thread extending below the central body portion, a bearing coaxial with said shaft intermediate said pedestal and said handwheel having a diameter greater than said handwheel thread, said bearing defining a cylindrical recess deep enough and wide enough to contain the portion of said handwheel thread extending below the central body portion Without contacting said thread, means non-rotatably keying said bearing to said shaft, and means releasably locking said bearing to said handwheel, whereby as said handwheel is rotated on said shaft, said shaft reciprocates with respect to said pedestal thereby adjusting the height of the chair body, and as said chair body is rotated with respect to said pedestal, the height of said chair body remains unchanged.

2. In a chair having height adjustment means, the improvement comprising a handwheel formed from a single continuous piece of sheet material, said handwheel having a substantially flat central body portion, said central body portion including a single helical thread integral at its root therewith, the apex of said thread defining a substantially circular opening adjacent the center of said central body portion, said thread extending below the plane of said central body portion, and a recessed bearing having a central bore concentric with said opening surounding, but not contacting, said thread, said bearing further contacting said central body portion adjacent said thread, and cooperating means on said central body portion and said bearing for releasably locking said bearing to said central body portion.

3. In a chair having a chair pedestal, a chair body rotatable with respect to said chair pedestal, and means supported by said chair pedestal for changing the height of the chair body with respect to the chair pedestal, height adjustment mechanism including a shaft upon which said chair body is supported and a helical thread integral with said shaft; a handwheel formed from a single continuous piece of sheet material threadedly engaging said threaded shaft; said handwheel including a body portion defining adjacent its center a single helical thread integral at its root with said body portion, the apex of said thread circumscribing a substantially complete circular opening in said body portion, said handwheel thread being of a pitch the same as the pitch of the shaft thread, and a vertical bore in said chair pedestal and surrounding at least a portion of said shaft, whereby when said handwheel is rotated, said threaded shaft is reciprocated with respect to said pedestal to adjust the height of said chair body, the

References Cited by the Examiner UNITED STATES PATENTS 1,261,232 4/18 Hibbard 151-21 1,501,180 7/24 Peters et-al 248-405 1,872,894 8/32 Collier et a1. 248-405 2,561,102 7/51 Elleman 248-188.1 2,567,884 9/51 Heath -85 2,572,588 10/51 Bedford 151-41.75 2,999,665 9/ 61 Ericson et al 248-405 3,044,165 7/62 Munse 29-532 3,046,828 7/ 62 Dzus 8536 3,108,371 10/63 Munse 29--532 CLAUDE A. LE ROY, Primary Examiner.

FRANK L. ABBOTT, Examiner. 

2. IN A CHAIR HAVING HEIGHT ADJUSTMENT MEANS, THE IMPROVEMENT COMPRISING A HANDWHEEL FORMED FROM A SINGLE CONTINUOUS PIECE OF SHEET MATERIAL, SAID HANDWHEEL HAVING A SUBSTANTIALLY FLAT CENTRAL BODY PORTION, SAID CENTRAL BODY PORTION INCLUDING A SINGLE HELICAL THREAD INTEGRAL AT ITS ROOT THEREWITH, THE APEX OF SAID THREAD DEFINING A SUBSTANTIALLY CIRCULAR OPENING ADJACENT THE CENTER OF SAID CENTRAL BODY PORTION, SAID THREAD EXTENDING BELOW THE PLANE OF SAID CENTRAL BODY PORTION, AND A RECESSED BEARING HAVING A CENTRAL BORE CONCENTRIC WITH SAID OPENING SURROUNDING, BUT NOT CONTACTING, SAID THREAD, SAID BEARING FURTHER CONTACTING SAID CENTRAL BODY PORTION ADJACENT SAID THREAD, AND COOPERATING MEANS ON SAID CENTRAL BODY PORTION AND SAID BEARING FOR RELEASABLY LOCKING SAID BEARING TO SAID CENTRAL BODY PORTION. 